Edge finishing machine



April 1951 E. c. OBERSTAR 2,550,289

EDGE FINISHING MACHINE Filed Sept. 9, 1948 f] l f ll I z I g 5 If 15 x6 28 z! is 15 m4 5 x2 7 12 1g Z4 Z0 o 0 2a Snventor 2% 2 6m a 648mm:

3 @QM W desired edge portions.

Patented Apr. 24, 1951 UNITED STATES PATENT OFFICE EDGE FINISHING MACHINE Application September 9, 1948, Serial No. 48,363

2 Claims.

The present invention relates to edge finishing machines and, more particularly, to improvements in machines for grinding and/or polishing the edges of sheets or plates of glass or other materials.

Broadly stated, the invention is primarily concerned with the provision of a controlling element for use in edging machines and which prevents the breaking or undesirable roundingof sharp corners which connect adjacent side edges of the sheets or plates to be edge finished.

This invention is especially well adapted for use on a type of edging machine wherein one or a series of sheets to be edged are carried in a vertical position along a substantially horizontal runway to move them over and in contact with one or a series of rotating grinding and/or polishing tools that are continuously urged upwardly toward the edges of the moving sheets or plates.

To illustrate, such machines are generally employed in edge finishin lights, that have been template cut from glass sheets or plates for use in automobile glazing, to provide the transversely rounded or pencil edge that is usually required for this work, such lights ordinarily include both straight and curved sides connected by either rounded or sharp corners.

Advances in edging technique have made it possible to automatically produce the desired rounded edge along the sides of the said sheets or plates of glass in sequence and without interruption between the ends of a continuous edging line. 7 7

However, when a sheet or light, or set of sheets or lights, are arranged for sequential grinding of the sides thereof on a machine of this character, and where two sides are joined by a sharp corner, it is necessary to restrain the normal upward movement of the edging tools to prevent their contacting the sharp corner of the light in a manner that will brea the corner, or obiectionably round it off, without, however, interfering with the surfacing of the adjacent edge to be treated.

To this end, there is provided, according to the present invention, a control element or lever which is adapted to engage the grinding tool or supporting portions thereof to properly position the periphery of the grinding tool'to grind the adapted to periodically engage and disengage the grinding tool to prevent advance grinding on a sharp corner of the sheets or lights without interfering with the subsequently occurring grinding operations to be effected.

The ontrol element is It is therefore an aim of this invention to provide an improvement for grinding machines of the above character which is primarily designed to control the operative position of a grinding wheel employed therein and for causing it to move in a desired path according to the particular edge contour to'be round.

Another important object of the invention is the provision of an actuatable element for controlling the positioning of a grinding wheel during initial grinding engagement with a moving work piece.

Another object is to provide a positioning element for a rotatable grinding tool which is adapted to be operated by work moving members and in advance of engagement between said tool and work whereby a leading edge of the work will have passed said wheel before grinding is effected.

Another object is the provision of an actuatable positioning element that is controlled by the advance of a work piece to a grinding wheel and whose influence is discharged in advance of completion of a. grinding operation.

A further object of the invention is to provide an a'ctuatable element for controlling the positioning of a grinding wheel, said element being adapted to adjustment whereby variations may be obtained in extent and duration of positional control.

A still further object of the'invention is the provision of a control element of, the character described for an edging machine which is of relatively simple construction, easy to assemble and adjust, positive inaction, efficient and durable in service and a general improvement in the art.

Other objects and advantages of the invention will become more apparent during the course of the following description, when taken in connection with the accompanying drawings.

In the drawings,f.wherein like numerals. are employed to designate like parts throughout the same:

Fig. l is a side elevation of an edging machine constructed in accordance with the invention;

Fig. 2 is a detail section taken substantially on the line 22 in Fig. 1;

Fig. 3 is a detail view of the and Fig. 4 is a top view of the control member as shown in Fig. 3.

Referring now more particularly to the drawing, the machine, generally indicated by the numeral I9, comprises a plurality of sections, similar to that shown in Fig. 1, wherein the sevcontrol member;

eral perimeter edges of a glass sheet II are progressively ground to produce a rounded or pencil edge. The Work is accomplished by carrying the sheets either singly or in sets, made up of several sheets arranged side by side, over a series of grinding wheels, one of which is indicated at I2, and whose periphery is grooved to the curvature required on the edges of the sheets.

In traversing the length of the machine, the sheets II are adapted to be moved continuously forward along a supporting runway, composed of rolls I3, and, in the specific instance shown above, the grinding wheel I2. Any suitable means may be provided for propelling the glass sheets forwardly, and the means herein shown comprising a pusher block I4 carried by a sprocket chain I5 and engaging the rear edges of the glass sheets. The sheets are maintained in a substantially vertical position and parallel relation by a guide member !5 which slides along a rail II secured to the framework I8 of the edging machine.

In passing through one or each of the several sections of said machine, the sheets I I are acted upon by the grinding wheels according to the manner of their location and mounting with respect to the machine and to the sheets. As herein shown, the wheel I2 is pivotally supported so as to contact and grind the lower edge of the sheets passing thereover. More particularly, the wheel is carried by a shaft It journaled in the ends 28 of a supporting arm M. The arm 2i is mounted by means of a shaft 22 on suitable bearings secured to the framework is and is conventionally counterbalanced, at its opposite end from the wheel, by a block 23 to offset the weight of the said wheel thereby permitting sufiicient engagement with the glass to effect grinding thereof without causing undesired lifting of the sheets from the supporting rolls I3. The wheel shaft I9 is conventionally operated by means of the motor 24 through a belt 25 trained about the motor pulley and a pulley 26 mounted on the shaft I9. Thus, as a sheet or set of sheets I I are borne into the. grinding area, their proximate edges are progressively ground to required shape as the wheel I2 contacts said edges. However, since the glass sheets are produced in a many, variant, template-cut outlines, it is not always desirable for the grinding wheel to ride into contact with the sheets at their leading corners and gradually descend until, as the sheets continuously move forwardly, the grinding wheel is in engagement with the lower edges.

Due to these variations in outline, as cut from plates or sheets of glass and, wherein some corners are rounded while others are sharp or sub stantially right angle in form, it has become necessary to provide an adequate element of protection. Such a protective means and which comprises the embodiment of my invention, is most advantageously employed in conjunction with a continuous grinding line wherein the sheets are periodically arranged so that their plurality of edges are ground in sequence. As a sharp corner of the sheet, as indicated at 21 in Fig. 1, approaches the grinding wheel it therefore is imperative that said wheel be removed from its position as shown in full line to that indicated in phantom line I2ct in order that grinding engagement is elfected at the corner only along the lower edge thereof.

I have found that this can be accomplished in an automatic manner by locating a special type of lever in operative position with reference to CJI the wheel to cause movement into operative relation therewith and thus depress said wheel as the glass sheets approach and move thereabove.

The lever, as indicated at 28, is pivotally mounted on a stud 29 which is extended through a side rail 39 of the framework I8. In order that adjustment may be made in the extent of movement with reference to the wheel I2, the lever is formed by a pair of plates 3i and 32, each carried on the stud 29 and interconnected by a lock bolt 33 located in a slotted aperture 34 in the plate 32. As shown in Fig. 3, the lever plate 3! has an arm portion 35 extended toward the shaft I9 of the wheel I2 while the plate 32 has a similar arm 36 extended angularly and outwardly from the arm portion 35. The end of the arm 9.6.is positioned so as to be contacted by a lug 31 supported in the linkage of the sprocket chain I5.

Preferably, the lug 3'! is located with respect to the pusher block it according to the length of the glass sheet and so as to be moved into engagement with the arm 33 of the lever 28 in advance of grinding contact between the said sheets and the wheel. As the lug rides onto the arm 36, the corresponding arm 35 acts to depress the grinding wheel until it reaches a position, as indicated at I2a, where it is maintained until the said wheel engages the lower edges of the glass sheets in grinding relation. Then, and until the rear corner of said sheets have been reached, the counterbalanced mounting of the arm 2I effects sufficient pressure to produce the desired edging in a manner Well known in the art. As the substantially straight area of the lower edge is traversed and the rear edge is moved into grinding relation, the wheel progressively rises along the rounded surface until separation is made by continuous forward travel of the glass sheets.

A stability of contact between the lug 3'! and the arm portion 36 of the lever 28 is maintained by a cover or upper rail 38 which is positioned above the normal elevation of the sprocket chain I5. The rail 38 is carried on brackets 39 secured to the side rail 33 and extends through the influential area of the lever to prevent ascent of the chain and consequent loss of pressure to be urged by the lug on the lever;

In the continuous movement of the glass sheets I I, the grinding wheel I2 is thus periodically depressed during their sequential entrance into the grinding area to locate the grinding surface thereof in line with the lower edge of said sheets. Subsequently, the depressing influence is removed as the lug 37 leaves its contacting engagement with the lever 28 and previous to passage of the rear corner of the sheets over the wheel. Since the intermittent control afiorded by engagement between the lug and lever is entirely automatic, use thereof is most advantageous in continuous edging machine lines wherein sets of glass sheets are ground on each edge and with little or no labor supervision intermediate the start and completion of the operation. It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred embodiment of the same, but that various changes in the shape, size and arrangement of parts may be resorted to without departing from thespirit of the invention or the scope of the subjoined claims.

I claim:

1. The combination with apparatus for treating the edges of plates or sheets including means 1 for supporting a sheet on edge for travel along a predetermined path, means for moving said sheet along the supporting means, an edge treating tool mounted adjacent and in alignment with said supporting means for movement into and out of the path of travel of said sheet, and means associated with the tool mounting means for normally urging said tool into the path of the sheet; of means for moving the tool relative to the path of the sheet and into position to treat an edgeof said sheet comprising a lever having divergent arms, means for mounting said lever with one of said arms in position to engage the mounting means for the tool and the other arm adjacent the path of the sheet moving means, and means carried by the sheet moving means and engageable with said other arm of said lever to move the tool when the sheet reaches a predetermined position.

2. The combination with apparatus for treating the edges of plates or sheets including means for supporting a sheet on edge for movement along a definite horizontal path, means for moving said sheet along said supporting means, an edge treating tool, means for mounting said tool below and in alignment with said supporting 6 means for swinging movement into and out of the path of travel of the sheet, and means associated with the tool mounting means for normally urging said tool upwardly into the path of the sheet; of means for moving the tool downwardly into position to operatively engage the lower edge only of said sheet comprising a lever having diverging arms, means for pivotally mounting said lever on said support with one of 10 said arms in position to engage the tool mounting means and the other arm adjacent'the path of the sheet moving means, and means carried by said sheet moving means for depressing said other arm of said lever to move the tool as said depressing means passes over the lever.

EDWARD C. OBERSTAR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,015,720 Louviaux Oct. 1, 1935 2,038,150 Weber Apr. 21, 1936 2,296,934 Kirkman et a1. Sept. 29,1942 

